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annotate spandsp-0.0.6pre17/src/spandsp/awgn.h @ 4:26cd8f1ef0b1

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import spandsp-0.0.6pre17
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Fri, 25 Jun 2010 15:50:58 +0200
parents
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26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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1 /*
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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2 * SpanDSP - a series of DSP components for telephony
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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3 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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4 * awgn.h - An additive Gaussian white noise generator
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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5 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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6 * Written by Steve Underwood <steveu@coppice.org>
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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7 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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8 * Copyright (C) 2001 Steve Underwood
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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9 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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10 * All rights reserved.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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11 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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12 * This program is free software; you can redistribute it and/or modify
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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13 * it under the terms of the GNU Lesser General Public License version 2.1,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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14 * as published by the Free Software Foundation.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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15 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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16 * This program is distributed in the hope that it will be useful,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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19 * GNU Lesser General Public License for more details.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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20 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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21 * You should have received a copy of the GNU Lesser General Public
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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22 * License along with this program; if not, write to the Free Software
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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24 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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25 * $Id: awgn.h,v 1.18 2009/02/10 13:06:47 steveu Exp $
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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26 */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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27
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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28 /*! \file */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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29
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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30 /* This code is based on some demonstration code in a research
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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31 paper somewhere. I can't track down where I got the original from,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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32 so that due recognition can be given. The original had no explicit
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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33 copyright notice, and I hope nobody objects to its use here.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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34
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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35 Having a reasonable Gaussian noise generator is pretty important for
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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36 telephony testing (in fact, pretty much any DSP testing), and this
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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37 one seems to have served me OK. Since the generation of Gaussian
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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38 noise is only for test purposes, and not a core system component,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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39 I don't intend to worry excessively about copyright issues, unless
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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40 someone worries me.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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41
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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42 The non-core nature of this code also explains why it is unlikely
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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43 to ever be optimised. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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44
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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45 #if !defined(_SPANDSP_AWGN_H_)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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46 #define _SPANDSP_AWGN_H_
26cd8f1ef0b1 import spandsp-0.0.6pre17
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47
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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48 /*! \page awgn_page Additive white gaussian noise (AWGN) generation
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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49
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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50 \section awgn_page_sec_1 What does it do?
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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51 Adding noise is not the most useful thing in most DSP applications, but it is
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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52 awfully useful for test suites.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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53
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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54 \section awgn_page_sec_2 How does it work?
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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55
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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56 This code is based on some demonstration code in a research paper somewhere. I
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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57 can't track down where I got the original from, so that due recognition can be
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
diff changeset
58 given. The original had no explicit copyright notice, and I hope nobody objects
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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59 to its use here.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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60
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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61 Having a reasonable Gaussian noise generator is pretty important for telephony
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
diff changeset
62 testing (in fact, pretty much any DSP testing), and this one seems to have
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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63 served me OK. Since the generation of Gaussian noise is only for test purposes,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
diff changeset
64 and not a core system component, I don't intend to worry excessively about
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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65 copyright issues, unless someone worries me.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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66
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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67 The non-core nature of this code also explains why it is unlikely to ever be
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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68 optimised.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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69 */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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70
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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71 /*!
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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72 AWGN generator descriptor. This contains all the state information for an AWGN generator.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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73 */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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74 typedef struct awgn_state_s awgn_state_t;
26cd8f1ef0b1 import spandsp-0.0.6pre17
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75
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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76 #if defined(__cplusplus)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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77 extern "C"
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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78 {
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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79 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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80
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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81 SPAN_DECLARE(awgn_state_t *) awgn_init_dbm0(awgn_state_t *s, int idum, float level);
26cd8f1ef0b1 import spandsp-0.0.6pre17
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82
26cd8f1ef0b1 import spandsp-0.0.6pre17
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83 SPAN_DECLARE(awgn_state_t *) awgn_init_dbov(awgn_state_t *s, int idum, float level);
26cd8f1ef0b1 import spandsp-0.0.6pre17
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84
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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85 SPAN_DECLARE(int) awgn_release(awgn_state_t *s);
26cd8f1ef0b1 import spandsp-0.0.6pre17
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86
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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87 SPAN_DECLARE(int) awgn_free(awgn_state_t *s);
26cd8f1ef0b1 import spandsp-0.0.6pre17
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88
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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89 SPAN_DECLARE(int16_t) awgn(awgn_state_t *s);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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90
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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91 #if defined(__cplusplus)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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92 }
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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93 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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94
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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95 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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96 /*- End of file ------------------------------------------------------------*/

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